Seeed Studio XIAO 7.5" ePaper Panel - Battery Status?

Products & Technology XIAO
2

Hi there,

SO you are correct , Home Assistant (HA) integration with Seeed’s XIAO 7.5" ePaper Panel doesn’t expose battery info by default. But the capability is there — it depends on how the firmware running on the XIAO is configured, and how it’s reporting battery voltage back to HA (e.g. via MQTT, ESPHome, or BLE).

You can add the voltage divider externally and then Analog read say (A3) along this line, and there are some threads here also on this topic.

For an S3,

Use a Resistor Divider from VBAT to an Analog-Capable Pin

Example:

  • Connect VBAT → 100kΩ → Analog Pin (e.g., A0)
  • Connect Analog Pin → 100kΩ → GND

This gives a 2:1 division, so a 4.2V battery reads as ~2.1V at the analog pin.

#define BATTERY_PIN A0  // or GPIO number

void setup() {
  Serial.begin(115200);
  analogReadResolution(12); // 12-bit ADC: 0–4095
}

void loop() {
  int raw = analogRead(BATTERY_PIN);
  float voltage = (raw * 3.3 / 4095.0) * 2.0; // adjust 2.0 if using a different divider
  Serial.printf("Battery Voltage: %.2f V\n", voltage);
  delay(10000);
}

For ESPHome add this YamL

sensor:
  - platform: adc
    pin: GPIO1  # or wherever your voltage divider feeds
    name: "Battery Voltage"
    update_interval: 60s
    attenuation: 11db  # for full range
    filters:
      - multiply: 2.0  # scale up for divider
    unit_of_measurement: "V"

the original question’s answer is "You will not see battery voltage unless their firmware explicitly uses an external voltage divider into an analog pin. Nothing is prewired on the Xiao ESP32-S3-based ePaper board for that.

HTH
GL :slight_smile: PJ :v:

FYI :crossed_fingers:

Board Built-in VBAT Monitor? Notes
XIAO nRF52840 :white_check_mark: analogRead(P0_31) or PIN_VBAT Has onboard VBAT divider
XIAO ESP32-S3 :x: None built-in Must use external divider
XIAO SAMD21 :x: None built-in External divider needed
XIAO ESP32C3 :x: None built-in External divider required

The old BSP for the Nrf52840 Xiao was able to read the battery voltage, check out the old threads on it, I have a demo of it there also.
non-embed and certain mbed BSP’s as well :pinched_fingers: